Past unsuccessful attempts to field precision-guided munitions have served
as hard lessons to U.S. Army developers, who are now trying to bring to fruition
a new generation of smart weapons.
Among the new weapons expected to enter service in 2008 is the Excalibur, a
satellite-guided artillery round that was drastically redesigned after several
test failures. To fix Excalibur, the Army joined forces with Sweden, which already
had developed a successful smart projectile. The U.S. contractor, Raytheon,
and the Swedish firm Bofors merged their designs, resulting in the current XM982
Excalibur made headlines two years ago when the Defense Department cancelled
the high-tech Crusader 155 mm howitzer, intended to replace the aging Paladin.
At the time, Pentagon officials said advanced munitions such as Excalibur were
more important than the guns themselves.
“The accuracy touted for Crusader really comes from Excalibur and not
from Crusader,” Deputy Defense Secretary Paul Wolfowitz told reporters
in 2002. Many artillery experts disagree, however, claiming that no matter how
precise a round might be, artillery units need a fast vehicle that can keep
up with the tanks and infantry carriers. A source of continuing debate within
the Army is whether artillery should serve in a “precision strike”
role, as opposed to its traditional “area suppression” function,
for which pinpoint accuracy is not as important.
In the absence of Crusader, the Army will fire Excalibur from a towed 155 mm
howitzer, now in development for the Army and the Marine Corps. The Paladin—with
1970s technology—may be too costly to upgrade for precision-guided rounds.
The Excalibur always was viewed as a complex technology, because its sensitive
electronics must survive a gun launch 15,000 times the force of gravity and
guide the projectile to a designated target, with a 10-20 meter accuracy from
ranges of about 40-43 kilometers. By comparison, the accuracy of conventional
artillery shells is about 270 meters.
The original design ran into trouble because the fins could not deploy properly,
making the round instable in flight. The Army then asked Raytheon to change
the weapon by incorporating the body and fin design of the Swedish “trajectory
The revamped Excalibur, to be purchased both by the U.S. and Swedish armies,
has been flying in tests.
“It appears to be working. The body is stable in flight,” said
Franklin Y. Hartline, Raytheon business development director for Excalibur.
Another major hurdle in this program was the hardening of the electronics,
which turned out to be more complex than anticipated. “The Army is playing
catch-up,” said Col. Nathaniel Sledge, Army program manager for combat
ammunition system. “Our systems have to be hardened. It’s not a
soft launch. … That is probably why we haven’t demonstrated this
Sledge said it’s important for the Army to field Excalibur successfully,
because the future of field artillery depends on its ability to incorporate
smart weapons into the arsenal.
“Artillery and mortars are more useful to the ground troops than close-air
support,” said Sledge. Excalibur would give the Army accuracy comparable
to the smart bombs used by the Air Force and the Navy, the Joint Direct Attack
Munitions. As is the case with close-air support, the Excalibur would be guided
to the intended target with the help of a forward observer.
The Army’s budget includes funding for 61,483 Excalibur projectiles,
but the quantity is likely to be revised based on weapon performance and cost,
Sledge noted. Ongoing cutbacks in field artillery units, mandated by the Army
chief of staff, also could affect the size of the program.
Raytheon projects the Excalibur will cost $29,000 each, once in production.
By comparison, conventional 155 mm rounds run about $4,000.
The Swedish version of Excalibur, meanwhile, is expected to be more technologically
advanced than the U.S. round, because it will be equipped with a data link,
so it can potentially be reprogrammed while in flight and hit moving targets.
The technology will allow a commander to transmit a signal to the projectile
in flight and redirect it to a different target location than the one originally
The U.S. Army may consider upgrading Excalibur with a data link in the future,
but not for the time being, according to Sledge.
Another Army official said that the service would not be in a position to take
advantage of that technology, unless the artillery infrastructure were upgraded,
such as the tracking radar and communications systems. “The Kingdom of
Sweden is developing that infrastructure,” the official said. “They
require in-flight retargeting for coastal operations against ships at sea.”
U.S. program officials are taking a more conservative stance, partly because
they don’t want to repeat the mistakes that led to the cancellation of
another Army smart weapon, the tank-killing Sadarm (sense and destroy munition).
Sadarm is an example of an advanced technology that, although effective, became
too expensive to make.
The Army ended the program after spending billions of dollars in research and
development, and only purchased a few hundred rounds.
During the invasion of Iraq last year, the Army shot 121 Sadarms, according
to Sledge. He said the employment of Sadarm in the field revealed how unprepared
the combat units are to use these advanced systems. “The hardware isn’t
enough,” said Sledge. The Army also needs “effective doctrine, tactics,
techniques and procedures” for how to operate smart weapons. Army units
in Iraq found themselves ill equipped to fire Sadarm, a weapon they never had
seen before, and had to request tactics and procedures guidance from the artillery
school at Fort Sill, Okla.
Interestingly, Fort Sill faxed the units a white paper that recommended 18-24
rounds per engagement. But the weapon was so successful in destroying enemy
armor that the units figured out they only needed three to four rounds to achieve
the “desired effects,” Sledge said. Unfortunately for the Army,
he said, the $300,000 weapon is unaffordable.